Klem — Tlie Development of Agaricocrinus. 



181 



VII. 

 1861. Agaricocrinus gracilis, Meek and Worthen. 



U. Burlington. 

 VIII. 



1860. Agaricocrinus Coreyi, Lyon and Casseday, 



Keokuk. 

 1882. Agaricocrinus 8pringeri, Keokuk. 



IX. 



1858. Agaricocrinus Wortheni, Hall. 

 1858. Agaricocrinus Whitfieldi, 

 1897. Agaricocrinus conicus. 



Keokuk. 

 Keokuk. 

 Keokuk. 



1855. 



1858. 

 1858. 

 1860. 

 1861. 

 1869. 

 1881. 

 1881. 

 1890. 

 1890. 

 1890. 

 1891. 

 1891. 

 1891. 

 1895. 

 1895. 

 1895. 

 1897. 



1897. 

 1897. 

 1897. 



Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 



Agaricocrinus 

 Agaricocrinus 

 Agaricocrinus 



Americanus, Koemer. 



tuber osus. 



bulla tus. 



pentagonus. 



excavaius, 



nodosus, 



crassus (?) 



elegans. 



Macadamsi, 



nodulosus, 



splendens. 



dissimilis. 



Gorbyi. 



Indianensis 



arcula. 



profundus, 



tugurium. 



Keokuk. 



Keokuk. 



U. Burlington. 



•U. Burlington. 



U. Burlington. 



U. Burlington, 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Keokuk. 



Americanus , var. tuberosus. 



Keokuk. 

 lowensis, Keokuk. 



KeoJcuJcensis. Keokuk. 



nodulosus f var. Macadamsi. 



Keokuk. 



In conclusion I will offer a few suggestions as to the fea- 

 tures which seem proper for specific separation. In the pre- 



